SOLUTION: Solve: "Determin "k" if -2 is a root of: 2x^2+ky+2=0

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Question 95134: Solve:

"Determin "k" if -2 is a root of:
2x^2+ky+2=0
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
"Determine "k" if -2 is a root of:
2x^2+kx+2=0
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If -2 is a root, f(-2)=0
f(x)=2x^2+kx+2
f(-2)=2(-2)^2+k(-2)+2=0
8-2k+2=0
-2k=-10
k=5
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Cheers,
Stan H.